Effects of ginseng supplementation on supramaximal exercise performance and short-term recovery.

The purpose of this study was to examine the effects of long-term ginseng supplementation on short, supramaximal exercise performance and short-term recovery. Using a double-blind protocol, 24 healthy, active women were randomly assigned to a ginseng (n = 12) or placebo (n = 12) treatment group. Each participant added a standardized extract of Panax ginseng C.A. Meyer (400 mg per day of G115) or placebo to their normal diet for 8 weeks (56-60 days). Before and after the trial period, each subject performed an all-out-effort, 30-second leg cycle ergometry test (Wingate protocol) followed by a controlled recovery under constant laboratory conditions. Nineteen subjects completed the study. Analysis of variance using pretest to posttest change scores revealed no significant difference between the ginseng and placebo study groups for the following variables measured: peak anaerobic power output, mean anaerobic power output, rate of fatigue, and immediate postexercise recovery heart rates (p > 0.05). In conclusion, the present data indicate that prolonged supplementation with ginseng (P. ginseng C.A. Meyer) has no ergogenic benefits during and in the recovery from short, supramaximal exercise.

Clinical recognition and management of patients exposed to biological warfare agents.

Concern regarding the use of biological agents (bacteria, viruses, or toxins) as tools of warfare or terrorism has led to measures to deter their use or, failing that, to deal with the consequences. Unlike chemical agents, which typically lead to severe disease syndromes within minutes at the site of exposure, diseases resulting from biological agents have incubation periods of days. Rather than a paramedic, it will likely be a physician who is first faced with evidence of the results of a biological attack. Provided here is an updated primer on 11 classic BW and potential terrorist agents to increase the likelihood of their being considered in a differential diagnosis. Although the resultant diseases are rarely seen in many countries today, accepted diagnostic and epidemiologic principles apply; if the cause is identified quickly, appropriate therapy can be initiated and the impact of a terrorist attack greatly reduced.

Bioterrorism.

Although biological agents have been used in warfare for centuries, several events in the past decade have raised concerns that they could be used for terrorism. Revelations about the sophisticated biological-weapons programs of the former Soviet Union and Iraq have heightened concern that countries with offensive-research programs, including those that sponsor international terrorism, might assist in the proliferation of agents, culturing capability, and dissemination techniques, and might benefit in these undertakings from the availability of skilled laboratory technicians. Release of sarin nerve agent in the Tokyo subway system in 1995 by the Aum Shinrikyo cult demonstrated that in the future terrorists might select unconventional weapons. Certain properties of biological pathogens may make them the ideal terrorist weapon, including 1) ease of procurement, 2) simplicity of production in large quantities at minimal expense, 3) ease of dissemination with low technology, and 4) potential to overwhelm the medical system with large numbers of casualties. Dissemination of a biological agent would be silent, and the incubation period allows a perpetrator to escape to great distances from the area of release before the first ill persons seek medical care. Countermeasures include intelligence gathering, physical protection, and detection systems. Medical countermeasures include laboratory diagnostics, vaccines, and medications for prophylaxis and treatment. Public health, medical, and environmental health personnel need to have a heightened awareness, through education, about the threat from biological agents.

Bioterrorism: agents of concern.

The intentional dispersal of biological agents by terrorists is a potential problem that increasingly concerns the intelligence, law enforcement, medical, and public health communities. Terrorists might choose biological agents over conventional and chemical weapons for multiple reasons, although it is difficult to predict, with certainty, which biological agents might prove attractive to terrorists. One can more confidently, however, derive a list of those few agents which, if used, would be of greatest public health consequence. It is these agents which will require the most robust countermeasures. We discuss the derivation of this short list of agents and the specific diseases involved.

A field-expedient algorithmic approach to the clinical management of chemical and biological casualties.

Warriors on the modern battlefield face considerable danger from possible attack with chemical and biological weapons. Aggravating this danger is the fact that medical resources at the lowest echelons of care, already likely to be strained to capacity during modern conventional combat, are at present inadequate to handle large numbers of chemical or biological casualties. Complicating this problem further is the austere nature of diagnostic modalities available at lower echelons. With this in mind, and given the urgency required to adequately manage chemical and biological casualties, it is likely that such casualties will initially require significant empiric care in the absence of a definitive diagnosis. Such care under field conditions, often rendered by relatively inexperienced medical personnel, might best be provided using an algorithmic approach. We have developed such an algorithm.

Immunization against potential biological warfare agents.

The intentional release of biological agents by belligerents or terrorists is a possibility that has recently attracted increased attention. Law enforcement agencies, military planners, public health officials, and clinicians are gaining an increasing awareness of this potential threat. From a military perspective, an important component of the protective pre-exposure armamentarium against this threat is immunization. In addition, certain vaccines are an accepted component of postexposure prophylaxis against potential bioterrorist threat agents. These vaccines might, therefore, be used to respond to a terrorist attack against civilians. We review the development of vaccines against 10 of the most credible biological threats.

Norwalk-like viral gastroenteritis outbreak in U.S. Army trainees.

An outbreak of acute gastroenteritis hospitalized 99 (12%) of 835 U. S. Army trainees at Fort Bliss, El Paso, Texas, from August 27 to September 1, 1998. Reverse transcriptase polymerase chain reaction tests for Norwalk-like virus were positive for genogroup 2. Gastroenteritis was associated with one post dining facility and with soft drinks.

Biological warfare. A historical perspective.

The deliberate use of microorganisms and toxins as weapons has been attempted throughout history. Biological warfare has evolved from the crude use of cadavers to contaminate water supplies to the development of specialized munitions for battlefield and covert use. The modern development of biological agents as weapons has paralleled advances in basic and applied microbiology. These include the identification of virulent pathogens suitable for aerosol delivery and industrial-scale fermentation processes to produce large quantities of pathogens and toxins. The history of biological warfare is difficult to assess because of a number of confounding factors. These include difficulties in verification of alleged or attempted biological attacks, the use of allegations of biological attacks for propaganda purposes, the paucity of pertinent microbiological or epidemiologic data, and the incidence of naturally occurring endemic or epidemic diseases during hostilities. Biological warfare has been renounced by 140 nations, primarily for strategic and other pragmatic reasons. International diplomatic efforts, including the 1972 Biological Weapons Convention, have not been entirely effective in preventing the enhancement and proliferation of offensive biological warfare programs. The threats posed by biological weapons are likely to continue into the future.

Delayed-type hypersensitivity skin testing in human immunodeficiency virus-infected pediatric patients.

OBJECTIVE: To evaluate whether pediatric patients infected with human immunodeficiency virus (HIV) can mount appropriate delayed-type hypersensitivity (DTH) skin responses to recall antigens and whether these responses can be correlated with clinical or immunologic parameters. DESIGN: Prospective evaluation of DTH responses in HIV-infected children. Uninfected children born to HIV-infected mothers served as control subjects. Antigens used for yearly DTH testing included Candida albicans (1:100, 1:10); mumps virus; Trichophyton; purified protein derivative of tuberculin; and tetanus toxoid (1:100, 1:10). At the time of each DTH test, patients were staged according to two Centers for Disease Control and Prevention pediatric HIV classification systems, and T-cell subsets were obtained. RESULTS: Twenty-seven HIV-infected patients with a median age at entry of 74.1 (range, 12 to 156) months were followed. Forty-four DTH skin tests in 21 symptom-free HIV-infected patients (PI) and 18 tests in 10 HIV-infected patients with symptoms (P2), as well as 43 DTH skin tests in 18 patients who had either mild or moderate clinical symptoms or immunosuppression and 19 tests in 13 patients with severe symptoms or immunosuppression, were evaluated. Sixteen DTH skin tests were performed in 14 uninfected patients. HIV-infected patients tended to have fewer DTH responses to antigens and of smaller size than did uninfected patients. When controlled for age, few differences in DTH responsiveness were seen between HIV-infected and uninfected patients. Anergy was associated with symptomatic disease, evidence of advanced clinical or immunologic disease, and low CD4+ percentages (p <0.05). CONCLUSIONS: HIV-infected children are able to mount antigen-specific cell-mediated immune responses that are qualitatively similar to those of age-matched control subjects. Loss of DTH responsiveness correlates with both clinical and immunologic evidence of HIV disease progression.

Pyogenic infections due to Ochrobactrum anthropi.

Ochrobactrum anthropi is a nonfermentative gram-negative bacillus that has been isolated with increasing frequency from human clinical specimens. Previously, its pathogenic niche was believed to involve the causation of catheter-associated bacteremic illnesses. We describe three cases of pyogenic infection due to O. anthropi, thereby expanding the known pathogenic potential of this organism.

Opsonic antibodies to Staphylococcus epidermidis: in vitro and in vivo studies using human intravenous immune globulin.

Staphylococcus epidermidis is a major cause of nosocomial infections, including sepsis in premature infants. Intravenous immune globulin (IVIG) has been used to prevent neonatal sepsis, but efficacy has varied in different clinical trials. The role of IgG antibody in immunity to S. epidermidis was studied using an opsonophagocytic assay and a lipid-emulsion-induced lethal model of neonatal S. epidermidis sepsis. Opsonic antibody to S. epidermidis varied between IVIG preparations and between lots: Lots with > or = 90% opsonic activity promoted bacterial clearance from blood and significantly enhanced survival when compared with lots with < or = 50% opsonic activity. Absorption of IVIG with S. epidermidis removed in vitro opsonic and in vivo protective activity. These studies suggest that opsonic antibody may play an important role in S. epidermidis immunity in immunocompromised patients, such as premature infants. Standard IVIG, however, may not provide therapy effective in preventing S. epidermidis infections, as many IVIG lots contain insufficient levels of opsonic S. epidermidis antibody.

Staphylococcus aureus meningitis associated with pyogenic infection of the sacroiliac joint.

Although we have reported the first case of Staphylococcus aureus meningitis due to pyogenic arthritis of the sacroiliac joint, this finding is actually not surprising, given the strong association between this form of meningitis and underlying bone, joint, and soft tissue infections. The physician faced with a case of meningitis due to S aureus in a patient without a history of trauma or neurosurgical manipulation must do a prompt and thorough search for underlying infectious conditions. In the case of sacroiliitis in particular, a high index of suspicion needs to be maintained, given the difficulties and delays in diagnosis associated with this infection. Radionuclide scanning with 99mTc or 67Ga is usually helpful in the early confirmation of this condition, the presence of which may be suspected on the basis of thorough physical examination.

Catheter-associated sepsis caused by Ochrobactrum anthropi: report of a case and review of related nonfermentative bacteria.

Ochrobactrum anthropi, formerly known as CDC group Vd, is an oxidase-producing, gram-negative, non-lactose-fermenting bacillus that oxidizes glucose and grows readily on MacConkey agar. Only occasionally isolated from human clinical specimens, this organism has rarely been found to be pathogenic. We describe the first reported case of infection due to O. anthropi in a child, that of bacteremia in a 3-year-old girl undergoing chemotherapy for retinoblastoma. In addition, we review the literature concerning cases of infection due to this and closely related bacterial species, namely Alcaligenes xylosoxidans subspecies xylosoxidans, Agrobacterium radiobacter, and "Achromobacter" group B. Finally, we attempt to clarify the confusing history and taxonomy of these organisms as well as make recommendations regarding antimicrobial therapy for infections caused by them.